Puzzle | The Burning Candles

Given two candles, each of which takes one hour to burn completely. They burn unevenly in different parts, though. You also have a box of matches. Using only these candles and matches, measure 45 minutes and 15 minutes.

Check if you were right - full answer with solution below.  

Solution:

Step 1: At 0 Minutes:

Starting at the same time,

• Light Candle 1 from both ends.
• Light Candle 2 from one end only.

Step 2: At 30 Minutes:

• Candle 1 burns out completely, as both its ends were burning.
• Candle 2 has been burning from one end for 30 minutes, so it has exactly 30 minutes' worth of wax left. Now light it from the other end.

Step 3: At 45 Minutes:

• Candle 2 had a remaining 30-minute worth of wax, so it burns in 15 minutes.

So, Candle 1 burning out measures 30 minutes, Candle 2 burning out measures the next 15 minutes, and together they total 45 minutes.